Speaking of ISO

[Basil]

This morning, just for fun, I decided to do a little unscientific ISO / Noise test with my 5D Mark IV. It's advertised as having pretty good high-ISO performance, so I just wanted to see how the noise was affected as I increased ISO. In this series of shots, I was in Av Mode at f4.0. I adjusted the ISO from 100 up to 32000. (somehow I skipped over 3200). I didn't adjust in fine increments as I just wanted to get rough idea of ISO/noise performance. Note the first couple images were very slow shutter and were hand held, so not the sharpest images to be sure. Note that all were shot in RAW but exported as .JPG, limiting the size to 3M so as to allow uploading here. The exception is the very last image. I shot that as JPG to see the effects of my in-camera "High ISO Noise Reduction" settings (which only works if you're shooting .JPG - no processing is done on RAW images). You can compare the last 2 pictures, both shot at 32000 and see a significant improvement when using High ISO NR. To my eye, the noise is acceptable all the way up to 6400. Even at 32000, when I used High ISO NR it isn't terrible. NOTE: If you click on an image it will open large to see noise better)

ISO 100


ISO 200


ISO 400



ISO 800



ISO 1600



ISO 6400



ISO 12800



ISO 25600



ISO 32000



THIS IS ALSO 32000 but shot as JPG with in-camera High ISO noise reduction
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[DrEntropy]

I can see no appreciable noise until you go past 1600. Even at 6400 you'd have to be looking for it to see any difference. And the last one with High ISO NR is impressive.

Haven't set up a definitive set of test shots to check ISO/noise ratio with these sensors, just arbitrarily decided to cap the ISO at 800 for now, thinking it (ISO) shouldn't be an issue. And still "untraining" my brain from old habits with the film cameras WRT controls themselves. SS and aperture adjustments not yet second nature. They need to be, with no hesitation.

 

[DrEntropy]

just arbitrarily decided to cap the ISO at 800 for now, thinking it (ISO) shouldn't be an issue.

Meaning that the ISO would be "static" as I mess around with exposure controls.

 

[Basil]

Meaning that the ISO would be "static" as I mess around with exposure controls.

Ok, when you said "cap" I was thinking something else. You're just basically setting the ISO at 800. On my 7D2 and 5D4, there is a setting that allows me to "cap" the ISO lower and upper ranges. So, if Im in Auto ISO, the ISO will adjust automatically as I change aperture and SS, but the ISO will never go below or above these settings. I keep my upper ISO set at 12800 most of the time. Anything higher and the noise becomes unacceptable.

 

[DrEntropy]

Ok, when you said "cap" I was thinking something else. You're just basically setting the ISO at 800. On my 7D2 and 5D4, there is a setting that allows me to "cap" the ISO lower and upper ranges. So, if Im in Auto ISO, the ISO will adjust automatically as I change aperture and SS, but the ISO will never go below or above these settings. I keep my upper ISO set at 12800 most of the time. Anything higher and the noise becomes unacceptable.

Sorry for the confusion. Your method with the "cap" on settings makes sense. My intent is that I know the "sensitivity" of the sensor at 800, the only variants are shutter speed and aperture to affect image outcome. Likely will use a similar scheme to yours later, when I stop moving controls the wrong direction first or use the wrong control for what I meant to change... it happened with that hawk when it lit off from the tree it was in, as it flew first into a bright sunlit space and all I got was its tail in-frame for fumbling with attempting to close aperture a stop or two. Wouldn't have happened with a film Nikon.

Kinda like coming back to CONUS after spending time driving "on the wrong side" and then having to consciously rethink which lane goes which direction. Getting it right more often now, so...